Determination of the State of the Practice in Travel Forecasting

This project will gather information and determine the state of the practice of metropolitan travel demand modeling by metropolitan planning organizations and state departments of transportation. The practice of interest includes such features of travel modeling as: (1) the size and scope of the transportation network and how it is represented; (2) population, employment, and land use forecasts and travel surveys and how they are generated and input into the modeling process; (3) how key model details, such as trip purposes, are represented, including how light-duty and heavy-duty commercial vehicle travel are modeled; (4) the nature, extent, and justification of model adjustments to fit unique local circumstances; (5) how congestion on networks is represented and how it is used as an input to mode choice models; (6) techniques and measures used in model estimation, calibration, and validation; (7) post-processing of travel demand modeling outputs to become inputs to emissions factor modeling; (8) feedback and model iterations; (9) induced travel demand; (10) staff capability and resources; and (11) unique conditions in individual areas.